JPH0831381B2 - Transformer - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer used in various audio equipment, video equipment, industrial equipment, and the like.

2. Description of the Related Art FIG. 9 shows a conventional transformer, and FIG. 10 shows a sectional view of the conventional transformer as viewed from the side. FIG. 11 is a sectional view of the conventional transformer seen from above, and FIG. 12 shows its output waveform. The configuration will be described with reference to FIGS. 9 and 11.

As shown in FIG. 9, the winding structure is the cylindrical portion 1 of the bobbin A with terminals.
The primary winding 17 and the tertiary winding 19 are wound between the middle flange 2 and the one end flange 3 provided on the other side, and further, between the other end 3 ′ and the middle flange 2, 2
This is a structure in which the secondary winding 18 is divided and wound by the intermediate collars 2a, 2b, 2c.

Generally, a switching transformer for an inverter used for a fluorescent lamp has a high frequency of several tens of kilohertz and a high output voltage of several kilovolts on the secondary side. Therefore, it is provided in the tubular portion 1 of the bobbin A with terminals. The structure in which the primary winding 17, the tertiary winding 19 and the secondary winding 18 are separated by the middle brim 2.

The manufacturing process will be described with reference to FIGS. 9, 10, and 11.

First, the primary winding and tertiary winding steps will be described. The primary winding 17 is wound a specified number of times between the middle collar 2 and the end collar 3 provided on the tubular portion 1 of the bobbin A. And the winding lead wire 17a,
The winding end lead wires 17b are respectively wound around the prescribed metal pin terminals 4a and 4b through the grooves 8b. Further, the tertiary winding 19 is wound on the primary winding 17, and the winding start lead wires 17c and 17d are wound around the specified metal pin terminals 4c and 4d through the grooves 8c and 8d, respectively.

Next, the secondary winding process will be described. The secondary winding 18 is wound a specified number of turns around the tubular portion 1 between the end flange 3'and the middle flange 2a. Further, it passes through the groove 9a provided in the middle collar 2a, and further, the specified number of turns is wound around the cylindrical portion 1 between the next middle collar 2a and the middle collar 2b. After that, a specified number of turns is wound around the tubular portion 1 between the middle collar 2b and the middle collar 2c through the groove 9b provided in the middle collar 2b. Then, the secondary winding 18 is completed by winding a prescribed number of turns through the groove 9c provided in the middle collar 2c and around the cylindrical portion 1 between the middle collar 2c and the middle collar 2. The winding start lead wire 18a is wound around the specified metal pin terminal 4e through the specified groove 8e. Winding end lead wire 18b
Is hooked on the protrusion 2c ′ provided on the middle collar 2c, and further the middle collar 2b
Of the metal flange 2a, and is then hooked by the protrusion 2a 'provided on the middle collar 2a and wound around the specified metal pin terminal 4f through the specified groove 8f. The coil thus completed has lead wires 17a-17d, 18a, wound around metal pin terminals 4a-4f,
Solder 18b to metal pin terminals 4a-4f. After that, the magnetic material 20 is further inserted into the iron core insertion hole 6 of the bobbin A with terminals to complete the transformer.

SUMMARY OF THE INVENTION This transformer is a bobbin A with a terminal having a structure in which a metal pin terminal 4 is implanted, and a tubular portion 1 is provided with several middle brims 2, 2a, 2b, 2c.
The primary winding 17 and the tertiary winding 19 are wound around the tubular portion 1 between the middle flange 2 and the end flange 3, and are wound around and connected to the respective metal pin terminals 4a to 4d. The secondary winding 18 has an end collar 3'and a middle collar 2
Between the intermediate flanges 2a, 2b, 2c provided in the tubular portion 1 between the two.
18b is hooked by a protrusion 2c 'provided on the middle collar 2c, then passes over the upper portion of the middle collar 2b, is further hooked by a protrusion 2a' of the middle collar 2a, and is then wound around and connected to the metal pin terminal 4f. The completed coil and the metal pin terminal are connected by soldering. After that, the transformer has a structure in which the magnetic material 20 is inserted into the iron core insertion hole 6 of the bobbin A with terminals to form a magnetic path, but there are the following problems.

This will be described with reference to FIGS. 3, 10, and 11. This transformer is a switching transformer used in an inverter circuit for lighting a fluorescent lamp as shown in FIG. 3, the operating frequency is as high as tens of kilohertz, and the output voltage is as high as several kilovolts. The voltage required for a fluorescent lamp is boosted by a transformer and taken out.

Therefore, the number of turns of the secondary winding 18 is as many as 1,000, and the wire diameter is a very fine wire. Referring to FIG. 10 below, the secondary winding 18
Since has a high voltage as described above, it is necessary to secure a constant space distance between the winding start lead wire 18a and the secondary winding wire 18 and the winding end lead wire 18b for the purpose of preventing a layer short circuit. Therefore, the winding end lead wire 18b is
8 and a middle tsuba with a height to secure a certain space distance
It has a structure in which it is hooked by a to 2c and then wound around and connected to the metal pin terminal 4f. That is, when the lead wire 18b at the end of winding sags, it comes into contact with the secondary winding 18 and a layer short circuit occurs.
Therefore, the winding end lead wire 18b must be constantly pulled between the metal pin terminal 4f and the middle collar 2c in order to maintain the space distance. That is, when the pin terminal 4f is bent due to a slight impact or the like, the lead wire 18b is pulled at the end of winding and a wire breakage occurs. In addition, the lead wire 18b at the end of winding is the middle collar 2
Since the structure of bridging between a to c or between the end flanges 3'is apt to be caught by the pin terminals or foreign matter, which may cause disconnection. Therefore, it is considered that the subsequent processes such as soldering, assembling the magnetic material 20, moisture-proof treatment, and inspection work particularly need not be in contact with the winding wire 18b at the end of winding, which is the reason why automatic assembly cannot be performed, and the cost is high. It was a thing.

Even for set makers, it is difficult to automatically mount the transformer on the printed circuit board for the above reasons, and when the set is subjected to impact, the transformer pins bend and the winding lead wires are pulled, causing a disconnection. Had a certain drawback.

Next, electric performance will be described with reference to FIGS. 11 and 12.

The primary winding 17 and the secondary winding 18 are separated by the middle collar 2. Therefore, when a current is passed through the primary winding 17, the magnetic flux 22 generally passes through the magnetic material 20 having a high magnetic permeability, but the frequency of use is high, and the bobbin has the structure as described above. Since they are separated in parallel by 2, the magnetic flux 20 does not pass through the magnetic material 20 like the magnetic flux 22, and a partial leakage magnetic flux 23 results.

Compared with the above-mentioned winding structure, the split type is generally referred to as the split type, and there is a lot of leakage flux, and the secondary winding is wound on the primary winding. It has drawbacks such as poor coupling between the two and a transformer with low efficiency. Further, the output waveform 28 on the secondary side also contains a harmonic component as shown in FIG. 12 due to the influence of the coupling degree or the leakage inductance, and as a result, it causes a decrease in the fluorescent lamp luminous efficiency or noise. Has been done.

As described above, the conventional transformer has a number of drawbacks such as quality, reliability, electric performance and cost.

Therefore, according to the present invention, a secondary winding that generates a high voltage is wound around a lower bobbin, an upper bobbin is covered thereover, and primary and tertiary windings are wound around the lower bobbin. The structure is such that the filler is injected more. Therefore, by adopting the above structure, the insulation distance between the primary winding and the secondary winding can be secured by the plastic molded product, and the limit breakdown withstand voltage can be improved, and the high pressure of the lower bobbin is further generated. By filling and impregnating the secondary winding with a filler, the limit breakdown withstand voltage between the primary winding and the secondary winding can be further improved, and the interlayer between the secondary windings can be improved. It is also possible to increase the level of withstand voltage. Furthermore, because the primary winding covers the entire secondary winding, the leakage flux is significantly reduced, the degree of coupling is improved, the efficiency is improved, and noise is not included in the output waveform. Can be realized.

Means for Solving the Problems The technical means of the present invention for solving the above problems is to provide a lower winding in which a high voltage is generated in a lower bobbin provided with notches for injecting a filler into the collars at the left and right ends. Winding so that the winding starts from the flange side and ends at the other flange side, and a pair of two-divided projections and shields for controlling the winding position on the tubular portion so as to cover the outer circumference of the lower winding. The upper bobbin of a plastic molded product with a plate or uneven thickness is fitted from above and below, the upper winding is wound around this upper bobbin, and the position corresponding to the notches on both ends of the lower bobbin. A magnetic material having a notch formed therein is incorporated to impregnate the lower winding with a filler.

Operation With the above configuration, the lower winding and the upper winding are completely insulated by the pre-stick molding, and the upper bobbin is wound at a position corresponding to the high voltage part of the lower winding of the lower bobbin. By controlling the winding position by providing wire position control protrusions, etc., it is possible to increase the insulation distance between the lower winding and the upper winding, which raises the level of the dielectric breakdown voltage and thus the life of the transformer. It will lead to improvement. In addition, the casting agent is cut by the notches on both ends of the lower bobbin and the magnetic material,
High voltage is generated by flowing into the lower winding of the lower bobbin and impregnating it between the lower inter-wires so that the inter-layer breakdown voltage between the lower windings or the insulation breakdown voltage between each winding. It is possible to improve the level of, and it is possible to further improve the life time. In addition, the fine winding wire is used for the lower winding of the high voltage, but since it is covered with the upper bobbin to protect the lower winding, it is not exposed on the surface and is not struck or caught in the post process. It is possible to reduce disconnection defects due to such factors. In addition, the lower winding has a structure in which the winding starts from the right end flange and ends at the left end flange.Therefore, the winding end lead wire does not fold back as in the past, so it does not float in the air and sticks to the bobbin. Can be reduced. Further, since the winding end lead wire does not pass over the wound coil, there is no need to consider the layer short between the winding start winding and the winding end lead wire of the lower winding. As a result, the insulation performance is improved between the lower windings under the high voltage use condition generated from the lower windings, and the life time of the transformer is significantly improved. As described above, this bobbin structure is a structure in which the lower winding, which is an ultrafine wire, is unlikely to cause disconnection. Therefore, post-processes such as winding soldering and core assembly can be performed smoothly, which improves yield and facilitates automation. Next, the electrical performance will be explained. The lower winding is wound on the lower bobbin, and the upper winding having a width close to the winding width covers the lower winding. The generated magnetic flux will pass through the winding width of the lower winding almost right underneath, and the leakage flux is much less than that of the split structure bobbin, resulting in a high degree of coupling, high efficiency, and noise reduction. Can have few transformers.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of an embodiment of the present invention, and FIG.
FIG. 3 is a sectional view of the present invention, FIG. 3 is a circuit diagram in which the transformer of the present invention is used, FIG. 4 is a perspective view of a lower bobbin and an upper bobbin of the present invention, and FIG. FIG. 6 is a perspective view of the lower bobbin seen from above, and FIG. 6 is a cross-sectional view seen from above of the present invention.
FIG. 7 is an output waveform diagram of the same transformer, and FIGS. 8a and 8b are perspective views of main parts of other upper bobbins.

 First, description will be made with reference to FIGS. 4 and 5.

The bobbin A with terminals has cylindrical portions 1a to 1d, and end flanges 3 and 3'are provided on the left and right ends thereof, respectively, and several metal pin terminals 4 are provided in a valued manner. Further, on both flanges 3 and 3 ', a groove 8 for wiring a lead wire and a projection 5 for hooking the lead wire are provided.
Is provided. Further, a notch 7 for injecting a filling material is provided at the upper end portion opposite to the flanges 3 and 3'at both ends, and the tubular portions 1a to 1d are provided with several intermediate flanges 2a to 2c. Tsuba 2a ~
2c is provided with grooves 9a to 9c through which lead wires pass.

Next, the upper bobbin will be described. This upper bobbin B
Is a structure divided into two in a pair, and the tubular portion 10
Collars 11 are provided on both left and right ends of the
Is provided. A wall plate 13 is provided on one of the cut surfaces, and a notch 14 for fitting the wall plate 13 is provided on the other end surface, and a hole 15 is provided on the cut surface of the outer periphery of the left and right flanges 11 at the other end. The structure is such that a protrusion 16 corresponding to the hole 15 is provided. The upper bobbin B having the above structure is inserted into the lower bobbin A described above from above and below, the wall plate 13 is inserted into the notch 14, and the projection 16 is fitted into the hole 15 to be integrally connected.

Next, the assembling method will be described. An example of a transformer circuit is shown in FIG. 3, where the primary winding 17, the secondary winding 18,
The secondary winding 18 is composed of a tertiary winding 19, and in particular, the secondary winding 18 has an output voltage required for a fluorescent lamp, so that it has a high voltage and a very fine wire diameter is used. First, the secondary winding process will be described with reference to FIGS. 1, 4, and 5. The winding start lead wire 18a of the secondary winding 18 as the lower winding is hooked on the protrusion 5a through the lead wire groove 8a and wound around the root of the metal pin terminal 4a. The secondary winding 18 is wound a specified number of times between the tubular portion 1a between the end collar 3'and the middle collar 2a, and further through the groove 9a provided in the middle collar 2a, the next middle collar 2a and the middle collar 2a. The cylindrical portion 1b of 2b is wound a specified number of times, and further passed through the groove 9b provided in the middle collar 2b. Subsequently, the specified number of windings are wound around the cylindrical portion 1d of the final middle collar 2c and the end collar 3 through similar steps. The winding end lead wire 18b of the secondary winding 18 thus wound is caught by the protrusion 5b through the lead wire groove 8b and wound around the base of the metal pin terminal 4f. Next, the outer peripheral portions of the flanges 11 on both ends of the upper bobbin B are connected to the lower bobbin A.
Both ends are fitted inside the collars 3, 3 ', and are press-fitted so as to be sandwiched from above and below to be integrated. The upper bobbin B is fitted in such a manner that the wall plate 13 fits into the notch 14,
Further, the protrusion 16 also joins and joins in such a manner as to enter the protrusion 15.

Next, on the upper bobbin B, the primary winding 17, 3 as the upper winding
The process of the next winding 19 will be described with reference to FIG. Similar to the process of the secondary winding 18 described above, the winding start lead wires 17a, 17b of the primary winding 17 pass through the lead wire grooves 8c, 8d of the lower bobbin A and are hooked by the protrusions 5 and then the metal pin terminals. It is wrapped around the roots of 4a and 4b.

Then, the primary winding 17 starts winding from the end flange 11 of the upper bobbin B, and the winding is completed after a specified number of windings. Winding lead wire 17c,
17d is hooked on the protrusion 5 through the lead wire grooves 8d, 8e of the lower bobbin A and wound around the bases of the metal pin terminals 4c, 4d. Then, the winding start lead wire 19a of the tertiary winding 19 is hooked on the protrusion 5 through the groove 8f and wound around the base of the metal pin terminal 4g, like the primary winding 17 described above. Then, the tertiary winding 19 is started from the protrusion 12 of the upper bobbin B, and the winding is completed by a specified number of turns. The finished winding end lead wire 19b is hooked on the protrusion 5 through the groove 8g and wound around the base of the metal pin terminal h. The winding is completed in the above process, and then the lead wires 18a, 18b, 19a, 19b, 17 wound around the metal pin terminals 4a to 4h are wound.
a to d are connected by soldering.

The subsequent steps will be described with reference to FIGS. 1, 2, and 4. The coil wound as described above and solder-connected to the metal pin terminals 4a to 4h has a notch 7 formed in the iron core insertion hole 6 of the lower bobbin A at both end flanges 3 and 3'of the lower bobbin A. The EI type or EE type magnetic material 20 having the notch 21 corresponding to is abutted and inserted.

After that, the magnetic material 20 is inserted into a protective case 24 made of plastics fixed with a tape or an adhesive agent.
Next, the filler 26 is injected from the case opening port of the coil in which the case has been inserted, penetrates into the magnetic agent 20, the windings 17, 18, 19, the lower bobbin A, the upper bobbin B, etc., and is further made of plastic. The bottom plate 25 is inserted and fitted to complete the transformer.

FIG. 2 shows a sectional view of the transformer after completion. The secondary winding 18, the primary winding 17, and the tertiary winding 19, which generate a high voltage, are the cylindrical portion 10 of the upper bobbin B of the plastic molded product.
For the purpose of regulating the winding position of the upper bobbin B at a position corresponding to the secondary winding 18 between the end flange 3'of the lower bobbin A and the middle flange 2a, which is completely insulated by and is the highest potential part. By providing the protrusion 12 so that the primary winding 17 or the tertiary winding 19 cannot be wound, by increasing the insulation distance between the high-potential winding of the lower bobbin A and the winding of the upper bobbin B. In order to raise the level of the insulation withstand voltage, and further the collars on both ends of the lower bobbin A 3,
Notch 7 is provided at 3 ′ and notch 21 is provided at magnetic material 20 and filler 2
By injecting 6 into the secondary winding 18 where a higher voltage is generated than the notches 7 and 21 and impregnating it between the windings, the withstand voltage between the wires of the secondary winding 18 or 2 Secondary winding 18 and primary winding 17,
The level of the withstand voltage between the tertiary winding 19 and the wire can be increased, and a highly reliable transformer can be realized.

On the other hand, as for the electrical performance, since the insulating structure is the fitting type, the primary winding can be wound directly above the secondary winding, and the winding widths of the primary and secondary windings can be made almost the same. That is, as shown in the sectional view of the present invention in FIG. 6, the magnetic flux 22 and the leakage magnetic flux 23 generated from the primary winding 17 pass through almost all of the secondary winding 18, and the leakage magnetic flux , Resulting in high coupling efficiency of the transformer and high efficiency, and the output voltage waveform 27 is
As shown in the figure, it was possible to obtain a transformer with few harmonic components and less noise.

The protrusion 12 of the upper bobbin B of the embodiment shown in FIG.
The same effect can be obtained by using the uneven thickness portion 12a of b or the shielding plate 12b.

EFFECTS OF THE INVENTION As described above, according to the present invention, a pair of plastics molded bombs obtained by dividing the upper winding and the lower winding are fitted to each other and integrally coupled to each other to further insulate, and further, a protrusion, a shield plate, and an uneven thickness. By increasing the insulation distance between the upper and lower windings by regulating the position of the upper winding by means of parts, etc., notches are provided on both ends of the lower bobbin around which the lower winding is wound. Since it is a so-called fitting type transformer with a structure in which the lower winding is impregnated by injecting the filling resin through the notch, that is, by dedicating the lower bobbin to the lower winding, the winding starts from one flange and the other Winding can be completed with the collar, that is, the winding end lead wire does not need to route the space between the middle collar of the bobbin, and a certain amount of tension is applied to prevent slack. Is completely unnecessary, and as a result, there is It is possible to reduce disconnection defects due to caution, contact with foreign objects, catching, hammering, etc., and to greatly reduce disconnection due to pin bending of the transformer in the set.

Since it is not necessary to fold back the lead wire at the end of the winding, automation of winding and wiring becomes easy. Next, the upper bobbin of the two-piece plastics provided with the protrusions for position regulation and the like is fitted and fitted together to be integrally connected, so that the insulating performance of the lower winding and the upper winding can be greatly improved. . In other words, the insulation structure is made completely of plastics moldings, and a protrusion for position regulation is provided at the portion corresponding to the high voltage part of the lower winding, and the upper winding of the upper bobbin is regulated to reduce the upper and lower windings. It is possible to increase the space distance between the windings, which leads to a significant improvement in the withstand voltage. Furthermore, since the lower winding is covered with the upper bobbin, the lower winding is not exposed,
Breakage defects such as catching are eliminated, and the subsequent winding, soldering, and assembly processes can be performed smoothly. Also, by filling the lower winding with a filler from the notches on both ends of the lower bobbin and impregnating it in the lower winding, the level of the insulation withstand voltage in the lower winding is increased, and further, between the upper windings of the upper bobbin. With this, it is possible to further improve the dielectric strength voltage.

Further, it is possible to reduce the leakage magnetic flux, to be efficient, to have less high frequency components as output, and to have less noise.

As described above, the final object of the present invention is to achieve a transformer having excellent disconnection quality, good efficiency, no noise generation, and excellent insulation with a bobbin fitting structure.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing the structure of a transformer according to an embodiment of the transformer of the present invention, FIG. 2 is a sectional view of the transformer, FIG. 3 is a circuit diagram of the transformer used, and FIG. Is a perspective view showing the structure of the bobbin of the present invention, FIG. 5 is a perspective view of the lower bobbin of the present invention seen from above, FIG. 6 is a sectional view of the same transformer seen from above, FIG.
Fig. 8 is the same output waveform diagram, Fig. 8a, b are perspective views of other upper bobbins, Fig. 9 is a perspective view of a conventional transformer, Fig. 10 is a sectional view of a conventional transformer, and Fig. 11 is FIG. 12 shows a cross-sectional view of the conventional transformer seen from above, and FIG. A: bobbin with terminal (lower bobbin), B: upper bobbin, 1 ... cylindrical part, 2,2a, 2b, 2c ... middle collar, 3,3 '... both ends collar, 4 ... metal Pin terminals, 5 ... Projections, 6 ... Iron core insertion hole, 7 ... Projections, 8 ... Lead wire groove, 9 ... Groove, 10 ...
… Cylindrical part, 11 …… End collar, 12 …… Protrusion, 13 …… Wall plate, 14…
… Notches, 15 …… holes, 16 …… projections, 17 …… primary winding, 18
…… Secondary winding, 19 …… Third winding, 20 …… Magnetic material, 21 ……
Notch, 22 ... Magnetic flux, 23 ... Leakage magnetic flux, 24 ... Protective case, 25 ... Bottom plate, 26 ... Filler, 27 ... Output waveform of transformer of the present invention.

Claims (1)

[Claims] 1. A cylindrical portion of a plastic molded product is provided in which a magnetic material is penetrated in the center and a lower winding for generating a high voltage is wound on the outer periphery, and a filler is injected into the outer peripheral portions of both ends thereof. On the lower bobbin provided with a collar with a notch,
The lower winding is wound so that winding starts from one flange side and ends on the other side, and the outer circumference of this lower winding is wound around the upper winding, which has flanges at both ends, facing the high voltage side. It is covered with a pair of upper half bobbins that are made of plastics and have a protrusion, a shield plate or an uneven thickness portion that regulates the line position.
A modification in which an upper winding is wound around this upper bobbin, a magnetic material is provided with notches at the positions corresponding to the notches on both ends of the lower bobbin, and the lower winding is impregnated with filler. vessel.